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Subject: Re: Red Laser Diode Rotating Drum Photo Plotter

From: "cunningfellow" <andrewm1973@...>
Date: 2006-04-29

> >andrewm wrote:
> > <SNIP>
> > There is going to be another Atmel sitting on
> > the end of a UART. You will simply X-Modem a
> > BMP file to it and like magic it should come
> > out the laser.
> >
> > I think this should be easy in assembly laguage
> > using the IN and POP instructions.
> >
> > Main_Routine:
> > IN Accumulator_A, XMODEM_Data
> > POP That_Data_Out_The_Laser
> >
> > As long as I can get that to assemble in AVR
> > studio the project should be finished tomorrow.

> Roger wrote:
> Hmm, missed this post before, yes it's the "like magic
> bit" that needs the algorithm!!


Damn - AVR Studio would not assemble that code :(

I will have to actually cut and paste some X-Modem CRC code
from my data loggers I build.

Now for the "POP That_Data_Out_The_Laser".......

I guess I am going to have to use a parallel to seriel
shift register (where will I find one of those in an
ATMega :).

So - We have :

An index mark from the opto encoder.
A pixel clock from the VCO on the 4046 PLL
A Laser we can pulse on and off
A parallel to seriel shift register
Some method of getting raster data from a PC
(via a TIFF file using CCIT group 3 fax)

I reckon I should be able to finish it in under 6
months.

It could be now that some unkind people would point
out that sometimes it takes me longer than 6 months
to mow my lawn :(